def ctz
import bend-collections-laws-crypto@1.0.0.0/src/math/f64.bend as F64import Base
import bend-collections-laws-crypto@1.0.0.0/src/math/u64.bend as W
import bend-collections-laws-crypto@1.0.0.0/src/math/w64.bend as X
1208def ctz(+w: W.U64) -> Nat:
1209 ctz_go(64n, w, X.odd(w))